Its not far from being able to do that, though. UE already has very well integrated, introspective build tooling - whats missing is an editor, basically, that

Its not far from being able to do that, though. UE already has very well integrated, introspective build tooling - whats missing is an editor, basically, that could handle the code-base of UE, and then .. wouldn't take much effort to integrate and complete the dynamic runtime/compiler-onboard loop.